Radiator



May 22, 19,45.y l J. F. BELAIEFF 2,375,749

RADIATOR Filed April 17, 1943 5 Sheets-Sheet l May 22, 1945- l J. F.BELAn-:FF 2,376,749

RADIATOR Fiied April 17, 1943 5 Sheets-Sheet 2 @f fm Patented May`22,1945 RADIATOR James Frank Belaieif, Gricklewood, London, England,assignor of two-thirds to Cyril Terence Delaney and Gallay, Limited,Cricklewood, London, England, a company of Great Britain ApplicationApril 17, 1943, Serial No. 483,453 In Great Britain January 16, 1942 6Claims.

This invention relates to plate heat exchange apparatus and moreparticularly to plate heat exchange apparatus of the kind known assecondary surface heat exchange apparatus.

Radiators for use in the cooling system of internal combustion'engineson aircraft must be designed to transfer the largest possible amount ofheat in relation to its weight and overall dimensions.

The resistancelto the flow of the cooling and coolant media must be keptas low as possible and the number of joints required must be kept downto the minimum in order to reduce risk of leakage.

The object of the present invention is to provide a new construction ofheat exchange unit which will embody as many as possible of the abovedesired features.

A heat exchange unit according to the present invention comprises aplurality of walls strutted in spaced relationship wherein the strutsdiffer in thickness between adjacent pairs of walls whereby the heatconductivity of the strut is proportional to the amount of heat requiredto be conducted thereby. One of the said walls may constitute a mainwall separating the two-media. Where two or more intermediate walls areprovided the thickness of the strut would be greatest between the mainwall and the rst wall and decreasing between each pair of successiveintermediate walls from the main wall.

The apparatus may comprise at least two adjacent main walls separatingcooling and coolant media, and at least two subsidiary walls situatedwholly in the cooling or coolant media and struts between said main andsubsidiary walls, wherein the struts between said main walls are thickerthan the struts between the subsidiary walls and the main walls wherebythe heat conductivity of the strut is proportional to the amount of heatrequired to be conducted thereby. The apparatus may comprise three ormore walls strutted together in spaced relationship, wherein one of saidwalls is a main wall separating cooling and coolant media and at leasttwo of said walls are in-` termediate walls situated wholly in one ofthe media wherein the thickness of the strut is greatest between themain wall and the first intermediate wall and decreasing between eachpair of successive intermediate walls from the main wall. The wallsthemselves which form partitions dividing up the space through which oneof the mediums is to circulate may vary in thickness, i, e., may bereduced in thickness the further it is positioned from a main wall, andmay differ in thickness from the corrugated strips.

In order that the invention may be more clearly understood, referencewill now be made to the drawings attached hereto:

Fig. 1 is a front elevation, and

Fig. 2 is a sectional plan on the line 2-2 of Fig. 1 of a radiator blockmade in accordance with the present invention :for use on an aircraft;

Fig. 3 is an enlarged sectional view through a portion of the blockshown in Fig. 1, and

Fig. 4 is a section on the line 4-4 of the portion shown in Fig. 3.

Figs, 3 and 4 are drawn on a much larger scale inorder to show theconstructional features.

Fig. 5 is an enlarged detail perspective view, partly in section andpartly broken away, of a portion of the heat exchange apparatus.

Fig. 6'is an enlarged detail sectional view illus trating a modificationof the invention.

In the form shown in the drawings, the radiator block comprises a numberof thin walls formed by metal plates 2 (see Figs. 3 and 4) held inspaced relationship by a corrugated strip 3. The plates are arranged inpairs with the corrugated strips between them, each pair of plates beingsealed at both edges in such a manner as to form a flat tube 4 (seeFigs, 1 and 2) equal in height to the height of the block and in widthto the thickness from front to rear of the block. The corrugated strip 3is soldered by the apices of the corrugations to the sidewalls 2 and ismitered in such a manner that it divides the space between them into aseries of V-shaped tubes through which the medium to be cooled isarrangedto flow.

Heat from the medium to be cooled will be transmitted to the wall 2either by direct contact with the wall or through the strip 3. Referenceto Fig. 1 will show that the block comprises a number of such tubes 4.Between the tubes 4 is the space to be traversed by the cooling mediumwhich in the case of the present radiator is, of course,air. This spaceis divided by two walls 5 and 6 arranged parallel with the tubes so thattioned between the wall 5 and the next main wall of the next tube 4. Asin the case of the tube 4 the corrugated strips l, 8 and 9 are securedby solder to the walls between which they are positioned so that theyhold the respective walls in spaced relation whilst at the same timeacting as conductors of heat. Since the strips 'l and 9 are in immediatecontact with a main wall of a tube 4 they are made of heavier gauge thanthe strip 8 which is between the two intermediate walls 5 and 6,likewise the intermediate walls 5 and 6 are of a lighter gauge than thewalls of the tube 4, the reason being that the further one gets from themain wall the less is the heat which has to be dissipated as all thisheat has to be conducted through the Walls and along the strips. Thestrips 1, 8 and 9 are arranged with their corrugations at right anglesto the corrugations of the strips 3 because the cooling fluid, inA thiscase, air, will be flowing in that direction. The strips 3, 1, 8 and 9respectively are, therefore, arranged so as to offer the leastpossibleresistance to the flow of the coolant and cooling medium respectively.

It is of course to be understood that the ends of the tubes 4 aresealedy into and are connected with the tanks at the top and bottom ofthe block as would be done in normal practice.

Although the invention has been described showing two intermediate wallsbetween the tubes 4 it must not be assumed that the. invention islimited to the use of two intermediate walls. Three or more intermediatewalls may be used and in some cases the further intermediate walls wouldgraduate in thinness as they recedey from the main wall as likewisewould the thickness or gauge of the corrugated strips which areinterposed between the respective walls. The tubes for the coolantliquid have been shown each with a single corrugated strip but it mustbe appreciated that the same construction could be applied if desired tothe passages formed by the said tubes for the coolant liquid as has beendescribed with reference to the passages for the cooling medium, that isto say that intermediate walls may be employed using different gauges.for the' intermediate walls and differing gauges for the interposedcorrugated strips. In the case where a single intermediate wall isemployed this may be thinner than the corrugated strip;

In the precise example shown the walls 5 and 6 and the strip 8 are .003"thickness whilst the strips 'l and 9 are .005 thickness, the walls 2.are.005 thickness and the strip 3 .003" thickness.

A further development of the principle ofthis invention illustrated inFig. 6 of the drawings consists in reducing the gauge of the corrugatedstrips and the intermediate walls along the direction of air flow, forexample, the corrugated strips may be made in sections such as 11, 12,13 of decreasing gauges and the intermediate walls may be built in smallsections such as 51, 52, and 53 of decreasing gauges. The thickeststrips are at the front of the radiator where the maximum heat transfertakes place, and the thinner strips being at the rear of the radiatorwhere the minimum heat transfer takes place.

It will be seen that by the present invention the most economical use ismade of the material, the heat conductors are proportional in .crosssectional area to the heat which they are required to conduct and thewhole structure is one of great strength whilst the joints are reducedto the barest minimum.

What I claim and desire to secure by Letters Patent is:

l. A radiator comprising at least two pairs of adjacent imperforate mainwalls coextensive in area with the main walls and forming coextensivespaces between them separating cooling and coolant media, and at leasttwo imperforate subl sidiary Walls situated wholly in the cooling orcoolant media and corrugated struts between said main and subsidiarywalls, the struts between said main walls being thicker than the strutsbetweenv the subsidiary walls and the main walls whereby the heatconductivity of the strut is proportional to the amount of heat requiredto be conducted thereby.

2. A radiator, comprising a plurality of walls strutted together bycorrugated strips in spaced relationship, one of said walls being amainwall separating cooling and coolant media and at least two of saidwalls being intermediate walls situated wholly in one of the media thethickness 0f the strut being greatest between the main wall and the rstintermediate wall and decreasing between. eachpar of successiveintermediate walls from the main wall for the purpose set forth, all ofsaid walls being imperforate and coextensive in area with one another.

3. A radiator, comprising a plurality of walls spaced apart to form aplurality of tubes and a plurality of channels between said tubes, allof said walls being coextensive in area with one another and with. thearea of the radiator and the channels and tubes being also coextensive acorrugatedstrip disposed in each of said tubes and channels and forminga strut device and the corrugated strips of the tubes and the channelsbeing arranged at right angles to each other, each of said stripsconsisting of a single layer of uniform thickness throughout its length,the strips in intermediate channels being of. less thickness than thestrips in channels adjacent the tubes.

4. A radiator as set forth in claim 3, the walls forming said channelsvarying in thickness.

5. A radiator as set forth in claim 3, the walls forming said channelsbeing reduced in thickness the further they are spaced from the wallsforming the tubes.

6. A radiator as set forth in claim 3, the walls formingsaid channelsbeing of different thickness from each other and from said struts.

JAMES. FRANK BELAIEFF.

